CameraITS: Update cv2 version check for 3.*

Open CV2 version has been updated to 3.4.2. In cv2image.py, we check
cv2 version for 3.2 thereby ignoring 3.4.2. Updated the version check
as "3." to include all versions in the 3.* range.

bug:197749094

test: Verified test_multi_camera_frame_sync after the fix.
Change-Id: I3009c9515ca9f14f27800f658e81141df7a5b486
2 files changed